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Process and an apparatus for the manufacturing of spiral drills

US 3,427,844 A · Inventors: BERGSTROM JOHAN ERIK

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Listed from its USPTO record in Patent Yard's full-term archive. Its claims, description and drawings are in the USPTO PDF and on Google Patents, and the Claude kit works from them.

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Why it's free to use

  • Granted February 18, 1969. A patent granted before 1976 lasted at most 17 years from grant, so its term ended by February 18, 1986.
  • We check US rights only. Old patents can still inspire new ones: improvements may be patentable.
FiledApril 23, 1963
GrantedFebruary 18, 1969
Term endedFebruary 18, 1986
Application number—
Classification (CPC)B21K5/04 +2 more
Length10 pages

Timeline

Timeline From USPTO dates

19641967197019731976197919821985Application filedApril 23, 1963Patent grantedFeb 18, 1969Term endedFeb 18, 1986

Sources & verification

Official USPTO records

Full published documentText and every drawing sheet as a PDF.USPTOFile historyStatus, office actions, notices, fee records and petitions.USPTO Patent CenterPatent Public Search recordSearchable full text and bibliographic data.USPTO

Cross-check elsewhere

Google PatentsFull text, worldwide family, citing patents and legal events.patents.google.comJustia PatentsFull text, claims and classification.patents.justia.comFreePatentsOnlineFull text and PDF.freepatentsonline.comEspacenetForeign family and legal status.European Patent Office

Everything on this page comes from the USPTO record linked above.